This invention is directed to a concrete composition that can be easily made from conventional materials in a ready-mix concrete plant and utilized to make temporary structures, especially flood control and erosion control berms.
Sandbags have been used to construct temporary berms to control flooding and erosion along creeks, streams, rivers, ponds and the like and around construction sites, especially construction sites having slopes. Classically, sandbags were made from canvass or gunny sack woven bags and filled with earth or sand. With time, the fabric of the cloth bags exposed to the elements would deteriorate exposing the contents of the bags to the elements which permitted the elements to slowly erode away the sandbag berm. In recent years, most of the sandbags have been made of polymeric bags, conventionally polyethylene bags which are frequently colored bright orange, bright red or black. The portions of the bag that are exposed to the elements, especially sunlight, deteriorate with time. However, the deterioration is not uniform and large pieces of the polymeric material remain or are scattered across the landscape by winds, water and the like. The portions of the cloth or polymeric bags that are covered by dirt or sand, are resistant to breakdown and will remain in the environment for many years if they retain a cover, even a thin cover of dirt.
Most local governments have enacted environmental regulations requiring that berms built up of sand bags must be removed after the need for the berm has disappeared. This is an expensive and time-consuming job as it requires that the bags be uncovered, emptied of their contents and collected.
Sometimes more permanent berms are prepared. These berms are prepared with earth to form a dam-like structure which is then covered with plastic sheeting or with a layer of asphalt or thin concrete. These types of berms present the same environmental problems that sandbags present. In fact, if asphalt or a thin concrete surface layer has been applied over the earthen berm, the tear-down of the berm is more costly because the concrete and asphalt must be collected and removed to a landfill area.
Another type of earth berm is prepared with earth which is then trenched out in the center to have a trench extending down about 3 to 6 inches into the firm earth. The resulting narrow trench is filled with concrete to form a support structure and backbone for the earth berm. Thus, when the berm is subjected to heavy water runoff, the earth portion of the berm may be eroded away leaving the concrete backbone to function as a wall. The berm in this case functions as a concrete form after the trench has been dug. The sidewalls of the berm and the portion of the trench dug into the underlying earth serve as form walls for the concrete. This type of berm, although very rugged and able to withstand substantial runoff over a lengthy period of time, is an expensive type of berm to break up after its need has disappeared. The concrete must be broken up and trucked away to a disposal site or order to return the landscape to its original form.
It is an object of the present invention to provide a new type of berm construction material which can be easily prepared in conventional ready-mix concrete plants. It is a further object of the present invention to provide a berm construction material which has sufficient strength to function as a floodwater and erosion control berm material. It is still another object of the present invention to provide a berm building material that can be easily broken up and allowed to return to the land without any environmental implications.